The hectic schedule of Sonny Bill Williams was complicated further when he was forced to put back his heavyweight fight with Francois Botha.

Williams, a rugby World Cup winner with the All Blacks a year ago, was due to meet Botha in Brisbane on November 24, but will now get into the ring with the South African next February on a date to be confirmed.

The reason given is surgery on chest muscle injury, and it remains to be seen if the rearranged fight will affect Williams' reported return to rugby league.

He is currently on a big-money, short-term deal with union side Panasonic Wild Knights, but is widely expected to join the Sydney Roosters for the new NRL season in March.

Commenting on his Twitter account, Williams said: "Just spoke to the doctor operation went well, Thanks for the support I've truly been blessed.. "